Hey Maksim, Tbh, my dog doesn’t like cabbage, he’s more of a chicken eating pet. If your dog likes cabbage that's not a problem, nonetheless you should try to maintain a proper diet for him. Only cabbage can be harmful. So try to come up with a balanced diet schedule - keep feeding cabbage but try to include other vegetables or chicken and fish as well. While preparing a diet chart for your dog, I recommend you to consult a professional. If you already have a vet, you can consult him/her. If not, you can search for one using any of these online portals - greatvet.com, goodvets.com, etc. You can connect with vets online and ask them suggestions and tips for the diet chart.